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CONNECTICUT 


4-3 


Agricultural  Experiment  Station 


NEW  HAVEN,  CONN. 


BULLETIN  230 


JUNE,  1921 


ENTOMOLOGICAL  SERIES,  No,  29 


THE  GRASS-FEEDING  FROG-HOPPER  OR  SPITTLE-BUG 


By  Philip  G  arm  ax 


Figure  17.     Spittle  balls  containing  nymphs  on  grass  stems 


CONTEXTS 


Page 
Officers  and  Staff  of  Station  .  .    326 
The  Grass-Feeding  Frog-Hop- 
per or  Spittle-Bug 327 

History 327 

The  Egg 328 

Table  Giving  Data  on  Length 

of  Egg  Stage 328 

The  Nymph 329 


Pape- 

Habits  of  the  Nymph ,.  330 

Composition  of  the  Froth 331 

The  Adult 331 

Description    of    the    Different 

Stages 332 

Control  iSIeasures    333 

Summarj- 334 

Literature 334 


The  Bulletins  of  this  Station  are  mailed  free  to  citizens  of  Connecticut 
who  apply  for  them,  and  to  others  as  far  as  the  edition  permits. 


CONNECTICUT  AGRICULTURAL  EXPERIMENT  STATION 

OFFICERS  AND  STAFF 
June,  1921. 


BOARD  OF  CONTROL. 
His  Excellency,  Everett  J.  Lake,  ex-officio,  President. 

James  H.  Webb,  Vice  President Hamden 

George  A.  Hopson,  Secretary Mount  Carmel 

E.  H.  Jenkins,  Director  and  Treasurer New  Haven 

Joseph  W,  Alsop Avon 

Charles  R.  Treat Orange 

Elijah  Rogers Southington 

William  H.  Hall South  Willington 


STAFF. 


Administration. 


E.  H.  Jenkins,  Ph.D.,  Director  and  Treasurer. 
Miss  V.  E.  Cole,  Librarian  and  Stenographer. 
Miss  L.  M.  Beautlecht,  Bookkeeper  and  Stenographer. 
Miss  J.   V.  Berger,  Stenographer. 
William  Veitch,  In  charge  of  Buildings  and  Grounds. 
Chemistry. 

Analytical  Laboratory.  E.  Monroe  Bailey,  Ph.D.,  Chemist  in  Charge. 
R.  E.  Andrew,  M.A.,  C.  E.  Shepakd,  -i 

H.  D.  Edmond,  B.S.,  Owen  L.  Nolan,  }  Assistant  Chemists. 
R.  T.   Mer-win,  J 

Frank  Sheldon,  Laboratory  Assistant. 
V.  L.  Churchill,  Sampling  Agent. 
Miss  Alta  H.  Moss,  Clerk. 

T.  B.  Osborne,  Ph.D.,  D.Sc,  Chemist  in  Charge. 

G.  P.  Clinton,  Sc.D.,  Botanist. 

E.  M.  Stoddard,  B.S.,  Assistant  Botanist. 

Miss  Florence  A.  McCormi^k,  Ph.D.,  Scientific  Assistant. 

G.  E.  Graham,  General  Assistant. 

Mrs.  "W.  W.  Kelsbt,  Stenographer. 


Protein  Research. 
Botany. 


Entomology. 


Forostrj. 


Plant  Breeding. 


W.  E.  Britton,  Ph.D.,  Entomologist;  State  Entomologist. 
B.  H.  Walden,  B.Agr.,  M.  P.   Zappe,  B.S.,    \    Assistant 
Philip  Garman,  Ph.D.,  >        Entomologists. 

John  T.  Ashworth,  Deputy  in  Charge  of  Gipsy  Moth  Work. 
Samuel  T.   Sealt,   Deputy  in  Charge  of  Mosquito  Control. 
Miss  Gladys  M.  Finley,  Stenographer. 

Walter  O.  Filley,  Forester 

A.  E.  Moss,  M.F.,  Assistant. 

H.  W.  HicocK,  M.F.,  Assistant. 

Miss  Pauline  A.  Merchant,  Stenographer . 

Donald  F.  Jon'es,  S.D.,  Plant  Breeder. 
P.   C.    Mangelsdorf,  Assistant. 


Press  op  The  Wilson  H.  Lee  Comp.iny. 


The  Grass-Feeding  Frog-Hopper 
or  Spittle-Bug 

•    {Philaenus  Uneatus  Linnaeus) 
Order  Hemiptera  Family  Cercopidae 

By  Philip  Garman,  Ph.D. 


Frog-hopper  or  spittle-bug  balls  are  often  observed  on  shrubbery 
or  herbaceous  plants,  in  waste  or  uncultivated  fields.  Those  of  the 
grass-feeding  species  are  especially  noticeable  in  meadows  and  may 
cause  persons  not  acquainted  with  them  to  speculate — often 
blindly — concerning  their  probable  nature.  Such  speculations 
are  mainly  confined  to  the  belief  in  "frog-spit"  and  "snake-spit," 
though  occasionally  we  find  people  who  think  them  the  young  of 
grasshoppers.  The  term  "frog-hopper,"  which  has  grown  out  of 
the  unfounded  belief  that  spittle  balls  are  voided  by  tree-frogs, 
is  not  inappropriate  when  applied  to  the  adult  bug  because  of  its 
squat  appearance  and  hopping  ability. 

In  favorable  locations  frog-hoppers  may  become  abundant  and 
no  doubt  do  considerable  damage.  In  one  instance  the  writer 
counted  fourteen  balls  on  grass  plants  within  a  square  foot,  which 
shows  the  relative  abundance  of  frog-hoppers  under  some  condi- 
tions. About  New  Haven  they  do  not  become  sufficiently 
numerous  to  do  serious  damage,  but  they  contribute  to  the  sum 
total  of  injury  caused  by  leaf -hoppers,  grasshoppers  and  thrips, 
and  may  be  counted  a  pest  for  this  reason. 

Frog-hoppers  are  sucking  insects  which  make  use  of  the  sap 
drawn  from  the  plant,  to  form  their  protective  spittle.  Any 
withdrawal  of  sap  in  this  way  naturally  weakens  the  plant,  and 
the  stem  upon  which  the  insect  has  fed  may  become  stunted  or 
may  not  produce  seed. 

Orchard  grass,  timothy,  red  top  and  blue  grass  are  infested  in 
Connecticut,  while  Osborn^  reports  it  also  from  Canada  blue  grass 
in  Maine.  The  adults  likewise  feed  on  grass  shoots  but  apparently 
do  not  do  as  much  damage  as  the  nymphs. 

Those  who  have  studied  the  life  histories  of  American  Cercopidae 
have  not  reported  direct  field  observation  of  the  egg  stage,  of  any 
of  them;  nor  have  they  followed  these  insects  through  their  com- 
plete cycle  from  egg  to  egg  or  adult  to  adult. 

Some  of  the  missing  links  in  our  chain  of  information  have  been 
observed  for  the  grass-feeding  spittle-bug  and  an  effort  has  been 
made  to  follow  it  through  its  life  cycle  by  observations  in  the  field, 
insectary  and  laboratory.     These  facts  are  herein  recorded. 

History 

Osborn^  studied  the  species  of  Maine  Cercopidae  and  his  observa- 
tions are  of  especial  value.     He  says  of  the  grass-feeding  species 


328         CONNECTICUT   EXPERIMENT    STATION    BULLETIN    230. 

that  it  lives  through  the  winter  in  the  egg  stage.  The  eggs  hatch 
late  in  May  or  early  in  June,  and  the  nymph  passes  through 
several  stages  (3-4)  before  the  adult  emerges.  Adults  were  ob- 
tained in  Maine  the  first  part  of  July  and  probably  mate  there  in 
August.  Egg  laying  is  extended  over  "some  weeks  in  autumn." 
Ball  in  his  summary  of  the  life  history  of  Cercopidae^  says  that  all 
species  except  one  pass  the  winter  in  the  egg  stage. 

The  Egg 

Confined  in  small  wire  cages  placed  over  grass  planted  in  flower 
pots,  the  adult  bugs  were  induced  to  mate  and  lay  eggs.  The  eggs 
are  laid  between  the  leaf  and  the  main  stem  (Fig.  18,  e),  are  usually 
placed  diagonally  to  the  stem,  and  within  two  or  three  inches  of 
the  ground.  They  are  firmly  attached  to  the  plant,  either  to 
leaf  or  stem.  As  many  as  eleven  have  been  found  in  one  group  but 
they  are  sometimes  laid  singly.  Cage  records  indicate  that  four 
or  five  are  usually  deposited  together. 

In  1920  eggs  were  obtained  on  the  following  dates  from  adult 
females  brought  from  the  field  and  mated  in  the  insectary: — 
July  12,  16,  25,  29;  August  2,  3,  5,  7,  8,  10,  11,  14,  15,  19,  21,  31; 
September  9,  12  and  20.  In  1921  the  first  eggs  were  obtained 
July  7,  but  could  probably  have  been  obtained  earlier  judging 
from  the  time  of  adult  emergence.  In  1920  adults  were  mated 
July  1,  but  no  eggs  were  obtained.  Of  the  eggs  obtained  in  1920, 
those  laid  on  July  19,  25,  29;  August  5,  6,  7,  12,  14,  26;  September 
7,  9  and  17,  hatched  the  following  spring,  the  period  of  incubation 
varying  from  228  to  281  days. 

Table  Giving  Data  on  the  Length  op  the  Egg  Stage. 

Length  of 
Eggs   Laid  Eggs  Hatched  Period   (Days; 

July  19,  1920 April  26,  1921 281 

July  25,  1920 May     6,  1921 275 

July  29,  1920 April  27,  1921 272 

August  5,  1920 April  30,  1921 268 

August  5,  1920 April  27,  1921 265 

August  5,  1920 April  27,  1921 265 

August  8,  1920 April  25,  1921 260 

August  7,  1920 April  30,  1921 266 

August^,  1920 April  26,  1921 261 

August  9,  1920 April  30,  1921 264 

August  10,  1920 April  20-26,  1921 253-259 

August  14,  1920 April  26,  1921 255 

August  14,  1920 April  25,  1921 254 

August  15,  1920 April  26,  1921 254 

August  14,  1920 April  26,  1921 255 

August  14,  1920 April  25,  1921 254 

August  31,  1920 April  26,  1921 239 

September  9,  1920 April  25,  1921 228 

September  12,  1920 April  28,  1921 228 

September  17,  1920 May     8,  1921 233 


GRASS-FEEDING   FROG-HOPPER   OR   SPITTLE-BUG.  329 

It  is  interesting  to  note  in  addition  to  the  fact  that  the  incuba- 
tion period  varied  from  228-281  days  in  1920-'21,  that  the  eggs 
laid  between  July  19-September  17  hatched  within  a  short  time 
of  one  another.  These  eggs  were  all  placed  out  of  doors  as  soon 
as  laid  and  brought  to  the  insectary  after  frost.  Furthermore,  it 
was  noted  in  field  cages  that  all  hatched  about  the  same  time  in 
1920;  viz.,  April  20,  and  that  young  were  first  seen  in  the  field 
about  this  time  both  in  shaded  and  exposed  situations. 

The  Nymph 

The  nymph  passes  through  four  instars,  and  the  nj^mphal  stage 
lasts  about  forty-five  days,  according  to  field  observations.  In  1920 
spittle  balls  were  observed  from  June  1  to  August  13,  though  most 
of  them  disappeared  about  July  4.  In  1921  n^inphs  were 
present  in  field  cages  from  April  20  to  June  14.  The  average  sum 
of  the  different  stages  obtained  in  the  insectary  totals  twenty- 
eight  days,  and  it  seems  probable  that  the  usual  period  lies  be- 
tween twenty-eight  and  forty-five  days  in  this  latitude,  though 
possibly  more,  or  less. 

The  first  stage  nymphs  hved  in  1921  from — 

April  27  to  May  10 13  days 

April  20  to  May    3 13  days 

April  26  to  May  11 15  days 

April  26  to  May  10 15  days 

April  26  to  May  11 15  days 

April  28  to  May  11 13  days 

April  26  to  May  11 15  days 

The  mean  hourly  temperature  in  the  insectarj^  during  the 
period  from  April  26  to  Maj^ll  was  56°  F;  maximum  76°;  minimum 
45°  F.  During  19  hours  of  this  period  the  temperature  registered 
below  50°  F. 

The  second  stage  collected  from  the  field  in  1920  lived  from: — 

June  8  to  June  12 4  days 

June  8  to  June  9    1  day. 

Data  on  this  sta|-e  are  ver}'  unsatisfactory.  Two  specimens  in  the 
third  instar  collected  from  the  field  in  1920  lived  from  June  8  to 
June  12,  four  days,  but  these  also  are  unsatisfactoiy  data. 

The  fourth  instar  in  1920  lived  from: — 

June  12  to  June  20 .  .  , 8  days 

June  9    to  June  20 11  days 

June  12  to  June  18 6  daj^s 

June  8    to  June  18 10  days 

June  8    to  June  15 7  days 

Osborn  reared  this  stage  in  Maine  in  2-6  days. 


330         CONNECTICUT   EXPERIMENT    STATION   BULLETIN    230. 

In  field  cages,  nymphs  hatched  about  April  20,  and  the  first 
adults  were  seen  June  14.  Insectary  temperature  during  this 
period  varied  from  45°  -  82°  F.  The  mean  hourly  temperature 
during  April  (April  26  to  May  1)  was  60.1°  F.,  during  May,  57.1°  F; 
and  during  June  (1-14)  60.3°  F.  For  about  60  hours  of  this  period 
the  temperature  was  below  50°  F. 

Habits  of  the  Nymph 

The  newly  emerged  nymph  has  a  yellow  spot  on  each  side  of  the 
abdomen.  These  spots  probably  mark  the  location  of  the  spittle 
glands,  the  openings  of  which  are  on  the  seventh  and  eighth  seg- 
ments. While  some  of  the  material  for  the  spittle  comes  from  the 
anal  opening,  a  great  part  must  come  from  these  abdominal 
glands,  the  substance  flowing  beneath  the  abdomen  where  it  is 
filled  with  air  bubbles.  The  apparatus  for  filling  the  mass  with 
air  bubbles  is  curious  and  is  connected  with  a  special  adaptation 
for  supplying  air  to  the  insect  itself.  In  young  nymphs  the 
ventral  surface  of  the  abdomen  is  covered  with  a  film  of  gelatinous 
material,  allowing  a  space  beneath  it  which  connects  with  the 
space  between  the  flap-like  plates  of  the  terminal  segments.  Air 
is  drawn  beneath  this  film,  the  insect  keeping  the  tip  of  the  abdo- 
men above  the  surface  when  quiet.  Spiracles  connecting  with  air 
tubes  are  located  on  the  ventral  surface,  between  pleura  and 
sterna  and  are  covered  by  the  film,  in  young  specimens,  and  by 
a  series  of  overlapping  plates — extensions  of  the  pleura — in 
older  ones.  The  insect  is  enabled  in  this  way  to  obtain  a  continual 
supply  of  air  and  at  the  same  time  remain  submerged  in  the  spittle. 
When  the  insect  desires  to  expand  the  froth  it  sticks  the  abclomen 
above  the  spittle,  encloses  an  air  bubble  within  the  two  terminal 
flaps,  brings  it  beneath  the  surface  and  forces  it  out.  Some 
species,  however,  are  able  to  work  faster.  Placing  the  tip  of  the 
abdomen  near  the  surface  of  the  spittle  they  roll  the  terminal  flaps 
together  rapidly,  taking  air  in  and  expelling  it  beneath  the  surface 
of  the  spittle,  at  the  same  time  moving  the  tip  of  the  abdomen  but 
little. 

Expansion  of  the  froth  with  air  serves  to  hide  the  nymph  and 
makes  excessive  secretion  unnecessary.  During  nymphal  life  the 
bug  may  construct  several  balls  but  there  is  usually  little  migra- 
tion after  the  first  mass  is  formed.  Moults  take  place  within  the 
froth  and  in  the  case  of  the  grass-feeding  frog-hopper,  the  adiilt 
also  develops  within  where  it  hardens  sufl&ciently  to  enable  it  to 
fly.  Thus  during  nymphal  life  at  least,  the  grass-feeding  spittle- 
bug  is  protected  from  predaceous  *  and  parasitic  enemies  and 
partly  from  adverse  climatic  conditions.  Lack  of  moisture  seems 
to  prevent  development  of  the  younger  stages  which  depend  largel}^ 
on  tender  rapidly  growing  shoots  as  a  food  supply.  The  result  is 
seen  in  their  more  frequent  occurrence  in  low  damp  places  than  in 
higher  well  drained  pastures. 


PLATE  XVIII 


a.     Spittle  balls  on  grass     About  natural  size      Photo  by  Walden. 


b.     Adult  bug.    Six  times  natural  size. 


c.     Eggs  on  grass.      Eight  times  natural  size.      Photo  by  Walden. 


PLATE  XIX 


a.     Field   with   spittle-masses.     Photo  by   Walden. 


A  '■'. — U       :  ■■ 

^^  ---.^i'rAv ■■■:■■ /.■■,,       / 

4^f M^ 

h^-^^\     -  •         /y'       V-.-       /                   '           '  ! 

<s.7..  ";"'■'  ^'P'  ./ 

HRDilMmi 

ms^ism 

<-%^t,^M\.vi^j:^-.,..:M 

b.    Grass  infested  with  frog-hoppers,  showing  spittle-masses.    Photo  by  Walden. 


grass-feeding  frog-hopper  or  spittle-bug.  331 

Composition  of  the  Froth 

Osborn^  says  that  the  froth  mass  is  only  partly  soluble  in  water. 
This  is  true  since  the  balls  often  remain  on  the  stems  after  showers. 
The  substance  is  more  readily  soluble  in  sodium  hydroxide,  but  is 
not  easily  soluble  in  80%  alcohol.  It  probably  contains  some 
starch  or  converted  sugar,  though  there  is  no  reaction  to  iodine. 
The  "albuminous"  substance  is  not  coagulated  with  heat.  The 
material  of  spittle  balls  offers  an  ideal  medium  for  molds  and  bac- 
teria which  may  sometimes  be  found  in  large  numbers. 

The  Adult 

Adults  were  collected  from  grass  plots  near  the  Station  from 
June  15  to  November  9,  1920,  and  specimens  were  taken  on  May 
29,  1921,  by  Mr.  Walden.  None  could  be  found  in  the  spring  of 
1921,  prior  to  May  29,  in  the  field  where  spittle  balls  and  adults 
were  numerous  in  1920.  None  of  the  adults  survived  in  field  cages, 
although  some  laid  eggs  which  hatched  the  following  spring. 
About  two  dozen  adults  in  a  field  cage  disappeared  completely 
during  the  summer  but  laid  eggs  which  hatched  about  April  20. 
Another  field  cage  contained  two  dozen  nymphs;  all  were  adult 
July  4,  and  they  lived  in  this  state  until  about  August  16,  when 
no  live  individuals  could  be  found.  Eggs  were  laid  by  these 
bugs,  and  recently  hatched  nymphs  were  found  April  20,  1921. 

The  adults  apparently  lay  but  few  eggs.  In  breeding  cages  not 
over  one  dozen  eggs  could  be  obtained  from  a  single  female, 
though  it  is  probable  that  they  may  lay  more  under  suitable  condi- 
tions. Most  individuals  laid  one  or  two  lots  of  eggs  consisting  of 
four  or  five  each,  and  then  died,  in  spite  of  efforts  to  keep  them  alive 
and  obtain  more  eggs.  Two  gravid  females  collected  in  the  field 
August  27,  contained  4  and  12  well  developed  eggs  respectively, 
while  two  others  collected  in  July  contained  0  and  4  eggs. 

The  period  elapsing  between  emergence  of  the  adult  and  egg 
lajdng  is  about  a  month.  In  1920  adults  were  obtained  in  the  field 
June  15  and  the  first  eggs  could  not  be  secured  until  July  12, 
although  attempts  were  made  several  times  previous  to  this  date. 
In  1921,  with  a  much  more  advanced  season,  freshly  emerged 
adults  were  taken  in  the  field  by  Mr.  Walden,  May  29,  and  the 
first  eggs  were  obtained  July  6  from  confined  bugs  brought  to  the 
insectary.  Mating  takes  place  from  the  first  of  July  until  October, 
at  least  in  this  locality. 

The  length  of  life  of  the  adult  in  field  cages  was  about  one 
month  and  a  half,  but  observations  on  unconfined  specimens 
indicate  a  longer  period — two  to  two  and  one-half  months  or  more. 
Thus  in  a  grass  plot  near  the  Station,  no  spittle  balls  were  seen  after 
the  first  of  July,  yet  adults  were  collected  here  until  November  9. 

Eggs  were  laid  in  small  cages,  within  two  or  three  days  after 
mating. 


332         CONNECTICUT   EXPERIMENT    STATION    BULLETIN    230. 

The  adult  bug  is  comparatively  sluggish  most  of  the  time.  It 
remains  on  the  stems  of  grass  plants,  and  is  not  easily  disturbed. 
If  poked  with  a  stick  it  moves  leisurely  up  or  down  but  never 
rapidly.  If  it  receives  a  more  violent  poke  or  blow  it  responds 
with  a  tremendous  hop,  landing  a  foot  or  more  away  from  the  origi- 
nal position.  If  followed,  it  will  usually  be  found  lymg  feet  up- 
wards on  the  ground  or  head  downwards  in  the  grass,  and  a  second 
blow  will  fail  to  react  on  it  until  it  has  had  time  to  regain  its 
feet.  _  The  bugs  are  most  active  towards  evening,  lying  almost 
inactive  during  the  morning. 


Figure  18.  The  egg  and  the  nymphal  instars  of  the  grass-feeding 
spittle-bug.  a.  First  instar.  b.  Second  instar.  c.  Third  instar.  d.  Fourth 
instar.    e.  Diagram  showing  the  usual  position  of  the  egg. 


Description  of  the  Different  Stages 

Egg  (Fig.  18;  PI.  XVIII,  c.)— The  egg  is  elongate,  slightly  curved  and 
flattened  a  little  and  is  usually  embedded  in  a  whitish  adhesive  substance. 
The  surface  is  smooth.  When  first  laid  it  is  nearly  white,  but  turns  light 
brown  with  age.      There  is  often  a  yellowish  tint  at  one  end. 

Total  length  about  .75-1  mm. 

First  Instar  (Fig.  18,  a.) — -This  stage  has  the  head  and  thorax  and  also 
the  legs,  dark  brown.  The  abdomen  is  yellowish  white  with  a  darker  yellow 
spot  on  each  side  below.  The  antennae  consist  of  two  distinct  divisions, 
the  distal  division  having  a  number  of  indistinct  annuli.  The  proximal 
division  has  two  indefinite  segments. 

Length  of  alcoholic  specimens  1.2-1.5  mm. 

Second  Instar  (Fig.  18,  b.)— This  instar  is  similar  in  nearly  all  respects 
to  the  first  instar  except  that  the  prothorax  now  lacks  brown  pigment. 


GRASS-FEEDING   FROG-HOPPER   OR   SPITTLE-BUG. 


333 


The  antennae  are  a  little  more  plainly  divided  into  segments  but  the  two 
main  divisions  are  still  evident.  The  yellow  spots  of  the  abdomen  are 
smaller. 

Length  of  alcoholic  specimens  2-3  mm. 

Third  Instar  (Fig.  18,  c) — During  this  stage  the  abdominal  yellow 
spots  disappear,  the  head  loses  its  brown  color,  and  the  wing  pads  are 
much  more  developed.  The  antennal  segments  may  now  be  counted  with 
ease. 

Length  of  alcoholic  specimens  3.5-4.5  mm. 

Fourth  Instar  (Fig.  18,  d) — This  stage  lacks  the  brown  color  of  the 
thorax  and  head,  the  entire  insect  being  pale.  Antennae  are  well  de- 
veloped, distinctly  segmented  and  not  separated  into  two  divisions  as  in 
the  first  and  second  instar.  The  wing  pads  are  well  developed,  now  ex- 
tending to  the  caudal  margin  of  the  first  abdominal  segment,  and  the 
sexes  are  easily  distinguished  with  the  aid  of  a  microscope. 

Length   (alcoholic  specimens)   5  mm. 

Adult,  male  (PI.  XVIII,  b) — Color  brown  with  a  pale  stripe  along  each 
side  on  the  costal  margins  of  the  elytra.  Head  brown,  eyes  black,  the  front 
below  marked  with  arcuate  black  lines;  lora  dark  brown  or  black.  Venter 
of  thorax  and  abdomen,  and  also  the  tarsal  claws  black.  There  is  usually 
a  darker  stripe  on  each  elytron  above  the  pale  costal  stripe.  The  hind 
legs  in  common  with  other  spittle-bugs  have  the  tibiae  and  first  two  tarsal 
segments  greatly  expanded  at  their  tips  and  spinose. 

Length  4.5-5.5  mm;  width  of  head  across  the  eyes  1.5-1.8  mm;  greatest 
width  across  the  elytra  when  folded  1.8-2  mm. 

Female  — -Similar  to  the  male  but  slightly  larger  and  the  elytra  less  de- 
finitely marked.  The  meso  and  metathorax  and  caudal  half  of  the  abdo- 
men below  are  pale  in  color. 

Length    5-6    mm. 


Figure  19.  Diagram  showing  the  length  of  the  various  stages  in  the 
life  history. 

Control  Measures 

Osborn  suggests  control  measures  for  the  grass-feeding  spittle- 
bugs,  which  seem  ample.  Rotation  of  crops,  or  burning  over  grass 
land  in  the  fall,  winter  or  early  spring  should  be  effective.  Hopper- 
dozer  control  would  probably  remove  many  of  the  adults  but  the 
latter  are  sluggish  and  it  is  doubtful  whether  the  method  would 


334  CONNECTICUT    EXPERIMENT   STATION    BULLETIN    230. 

capture  a  large  per  cent.  Mowing  in  spring  and  fall  unless  very 
close  to  the  ground  and  the  grass  raked  off  soon  after,  would  also 
be  ineffective  because  of  the  position  of  the  eggs.  If  the  grass  is 
allowed  to  lie  on  the  ground  the  nymphs  will  soon  crawl  from  the 
cut  grass  to  fresh  stems. 

Spraying  is  too  costly  an  operation  to  be  of  much  use  in  practical 
control  work.  Dusting  might  be  done  effectively  under  some 
conditions  though  it  is  well  nigh  impossible  to  get  action  from 
any  insecticides  owing  to  the  protective  spittle. 

Summary 

1.  The  grass-feeding  frog-hopper  may  cause  considerable 
damage  to  grasses  in  meadows. 

2.  The  life  cycle  lasts  a  year,  the  greater  part  of  which  is 
passed  as  an  egg  laid  during  the  summer  and  fall. 

3.  The  eggs  are  laid  between  a  leaf  and  a  stem,  being  usually 
placed  4  or  5  together,  and  within  two  or  three  inches  of  the 
ground. 

4.  The  adults  are  found  in  the  field  from  June  until  frost, 
laying  eggs  over  a  considerable  period  (July-October). 

5.  The  nymph  passes  through  four  stages,  and  lives  about  a 
month  and  a  half.    Nymphs  hatched  in  1921  about  April  20. 

6.  Control  measures  should  consist  of  burning  over  the  land 
during  fall,  winter,  or  early  spring. 

Literature 

1.  Ball,  E.  D.,  Ann.  Ent.  Soc.  Amer.,  XIII;    143;    1920. 

2.  Fernald,  C.  H.,  Mass.  (Hatch)  Exp.  Sta.  Bui.  12;  9-11;  1891. 

3.  Lintner,  J.  A.,  4th  Report  of  N.  Y.  State  Entonaologist  1887;  p. 
240-241. 

4.  Lintner,  J.  A..  5th  Report  of  N.  Y.  State  Entomologist  1888;  p.  245. 

5.  Osborn,  H.,  Maine  Agr.  Exp.  Station,  Bui.  254;  273-277;  1916. 


Note: — This  bulletin  properly  belongs  in  the  report  for  1921,  but  owing 
to  delay  in  issuing  the  jeport  for  1920,  it  is  here  included  to  secure  its 
earlier  publication. 


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